Certain turbo-engines have a rotor formed of a disk and vanes provided with feet intended to be engaged in axial or slightly oblique broachings established at the periphery of the disk. It is then vital to provide means to stop the feet from sliding to a position which would obstruct the clearances existing between the feet and the surfaces of the broachings which could constitute bypass passages for the gases which circulate in the turbo-engine, thus resulting in adversely affecting the efficiency of the latter. Therefore, sets of joints or flanges of varied designs have been provided, one example being described in the U.S. Pat. No. 4,846,628. The joints and the flanges are retained against any axial movement by means of grooves or small tongues situated on the vanes and the disk. They also need to be retained against a radial extension movement which the centrifugal forces tend to produce. The result of these stresses of the joints and flanges cause them to assume a relatively complicated shape which makes it frequently delicate to place the latter, especially if they need to be deformed.